Carburetion system



Apm il?, 19M H. J. MCLEOD CARBURETION SYSTEM 2 Sheets-Sheet 1 Filed Jan.13, 1948 INVENToR. 7e

April 17, 1951 H. J. MCLEOD 2,548,989

CARBURETION SYSTEM Filed Jan. 13, 1948 2 Sheets-Sheet 2 INVENTOR.

faQ/7 Eff/M356@ Patented Apr. 17 1951 UNITED STATES PATENT OFFICECARBURETION SYSTEM Henry J. McLeod, Gary, Ind. Application January 13,1948, Serial No. 2,072

6Claims.

l This invention relates to improvements in liquid fuel carburetingsystems for internal combustion engines, and more particularly to such asystem for producing gas from liquid fuel, such as gasoline, for theoperation of variable speed internal combustion engines, the primaryobject of the invention being to provide a highly practical and eicientsystem of this character which is relatively compact and simple instructure and in operation, and can be produced at relatively low costfor devices of this character.

Another important object of the inveition is the provision of acarbureting system of the above-indicated character which provides moreeconomical and eicient utilization of liquid fuel, whereby substantialeconomies are obtained when aconventional carburetor is replaced by sucha carbureting system.

Another important object of the invention is to provide a carburetingsystem of the character indicated above which supplies air-mixed gas,

derived from a conventional liquid fuel supply,

. for the operation of an internal combustion engine, instead of theair-mixed, merely atomized liquid supplied by conventional curburetingsystems, the desired results being achieved by progressively more finelyatomizing the liquid fuel in the presence of heat, mainly derived fromthe engine, until the fuel assumes the form of gas in advance of itsdelivery to the carburetor of the system for charging the engine.

Other important objects and advantageous features of the invention willbe apparent from the following description and accompanying drawings,wherein, for present purposes of illustration only, a specic embodimentof the invention is set forth in detail.

In the drawings:

Figure 1 is atop plan view.

Figure 2 is an enlarged transverse vertical section taken on the linev2-2 of Figure 1.

Figure 3 is a horizontal section taken through the primary and secondaryvaporizing and heating chambers.

Figure 4 is an enlarged fragmentary horizontal section taken through thesecondary chamber and its air inlet valve.

Figure 5 is a transverse vertical section taken through the carburetortube and primary and secondary chambers.

Figure 6 is a side elevation taken at right angles to Figure 5 with theprimary chamber in vertical longitudinal section.

Referring in detail to the drawings, the numeral 1 generally designatesa Vertical carburetor tube provided at its upper end with an air filterand having a ange 8 at its lower end for bolting, as indicated at 9, tothe engine intake manifold Ill in the usual way. In the lower part ofthe carburetor tube is a butterfly-type speed valve II on a horizontalshaft I 2, and in the expanded upper part 1' ofthe tube a butterflytypechoke valve I3 on a horizontal shaft I 4.

On a level between the valves II and I3 and near the expanded tubeportion 1', and axially aligned at right angles to the shafts I2 and I4, a stud I5 and a tubular tting I6 are threaded into opposite sides ofthe carburetor tube, the stud I5 acting solely as support for theprimary atomizing and heating chamber I1, and the fitting I6 acting assupport for the secondary atomizing and heating chamber I8, and also asthe means for charging the carburetor tube 1 with gaseous fuel from thesecondary chamber.

The primary chamber I1, as shown in Figures 3 and 6, is cylindrical andhorizontally elongated, comprising an outer, preferably aluminum,cylindrical shell I 9 covered with heat insulation 20, such as asbestos,with the stud I5 threaded into one side of the shell, with insulatedmaterial rings 2I set into and closing the opposite ends. Cup-like metalheads 22 are set into the rings 2! and supportably receive and close theopposite ends of a metal cylinder 23, the cylinder 23 thereby beingsubstantially spaced from the shell I9 so as to del-lne an engineexhaust gas chamber 24. The heads 22 are axially traversed by liquidfuel atomizing jets 25, to which are connected branch fuel lines 2Bleading from opposite sides of a T-fitting 21 connected with the liquidfuel line 28 leading from the fuel pump 29 which draws liquid fuel, suchas gasoline, from the fuel tank 30. The pressure exerted by the pump issuicient to cause the jets 25 to fill the cylinder 23 with atomizedliquid fuel, and to cause the atomized fueltherein to pass upwardlythrough a T-tting 3l having its standard 32 passing through the top ofthe shell I9 and threaded into the top of the cylinder 23, as shown inFigure 5, and having heated tubes 33 leading from its cross-head 34 andconnected to open-fittings 35 in the opposite ends of the secondarychamber I8.

The heated tubes 33 are Wound with wire electric heating elements 36,and an outside asbestos covering 31, one end of 'the coils 36 beingtogether connected to a wire 38, and the remaining ends of the coilsbeing together connected to a wire 39, these wires being suitablyconnected to lend thereof.

the electrical system (not shown) associated with the engine (notshown).

The secondary chamber I8 is the same in construction as the primarychamber Il, except for the absence of the T-iitting 3l, and has an airinlet valve 38 traversing the outer side thereof, as shown in Figure 4.The air inlet valve 38 may be of any suitable adjustable needle-typewith the axial needle 39 adjustable in the tubular valve body 40 whichpasses through the outer shell I9 and connects at its inner end with thecylinder 23', by means of an apertured boss 4l with its bore 42 openinginto the interior of the cylinder 23.

For supplying engine exhaust gas to the spaces 24 of the chambers l1 andI8, a pipe 43 leads from the engine exhaust manifold 44 at a forwardpoint and has branches 45 which open through the bottom of the outerchamber shells I8 near one Outlet branch pipes 46 lead from the oppositeends of the outer chamber shells to carry off the exhaust gas to a pipe4T which is connected to a rearward point of the engine exhaust manifold44.

The above-mentioned tubular fitting i6, supporting the secondary chamberI8 on the carburetor tube 1, extends radially through the outer shellI9, as shown in Figures 3 and 5, at a point intermediate the ends of thechamber, and has its radially-inward end connected to a tubular boss 48by means of which the fitting l5 communicates with the interior of thecylinder 23', so that the fuel gas Vformed in the cylinder 23 can passtherefrom into the carburetor tube l for charging into the engine intakemanifold l0.

A liquid fuel drain pipe 49 traversing the lower side of the primarychamber Il leads from the bottom of the cylinder 23 to the fuel line 28to drain away any liquid fuel Which might otherwise accumulate in thecylinder 23 while the system is not in operation. Another drain pipe 50traversing the lower side of the secondary chamber I8 leads from thebottom of its cylinder 23' through a point l on the .adjacent side ofthe carburetor tube 1 at the juncture of the lower end of the carburetortube with its flange S, so that any vapor which may condense in thecylinder 23' while the engine is inoperative may drain oif into theengine manifold 44.

In operation, the engine with which the abovedescribed system isassociated being in operation, the fuel pump 29 draws liquid fuel, suchas gasoline, from the tank 3B, and forces the liquid through the mainfuel line 28 with sufficient pressure to cause the primary chamber jets25 to atomize and spray liquid fuel in the interior of l the cylinder23. The cylinder 23 being heated by engine exhaust gas in the space 24,the atomized fuel is warmed as it passes from the cylinder 23, andfurther warmed as it passes through the electrically-heated tubes 33 onits Way to the secondary chamber. The heated liquid fuel in atomizedcondition is drawn into the secondary cylinder 23 through theconnections 35 in such a fine mist that the heat of the cylinder 23',derived from the engine exhaust gas-heated space 24', is sufficient `toturn the mist into gas, under sufficient pressure to pass through thefitting it into the interior of the carburetor tube 1. To render the gasproduced in the secondary chamber adequate for combustion in theassociated engine, sufficient air for admixture to the gas is admittedinto the cylinder 23' through the air inlet valve 38, adjustment of theneedle 39 determining an efficient air and gas mixture.

I claim:

l. In a device for supplying a mixture of airl and vaporized liquid fuelto the tube of a carburetor of an internal combustion engine having anexhaust manifold, said device comprising a primary chamber for heatingliquid fuel and having atomizing jets at its opposite ends, a liquidfuel force pump connected in supply relation to the jets of said primarychamber, an outlet intermediate the ends of said primary chamber, asecondary chamber having openings at its opposite ends connected to saidoutlet for further atomizing the fuel received from said primarychamber, said secondary chamber having an outlet intermediate its ends,means adapted to be connected in communication with the exhaust manifoldof the engine arranged in heating relation to both of said chamberswhereby fuel present in said primary chamber is warmed prior to enteringsaid secondary chamber and whereby the further atomized fuel present insaid secondary chamber is sufficiently heated to pass into gaseous form,an outside air inlet intermediate the ends of said secondary chamber foradmitting air for admixture to the gas present in said secondarychamber, and a conduit leading said outlet of the secondary chamber andentering said carburetor tube for conveying the gas and air mixture intothe carburetor tube, a choke valve in said carburetor tube above thepoint of entrance of said conduit in said carburetor tube, and a speedvalve in said carburetor tube below said point of entrance of saidconduit.

2. In a device for supplying a mixture .of air and vaporized liquid fuelto the tube of a carburetor of an internal combustion engine having anexhaust manifold, said device comprising a primary chamber for heatingliquid fuel and having atomizing jets at its opposite ends, a liquidfuel force pump connected in supply relation to the jets of said primarychamber, an outlet intermediate the ends of said primary chamber, asecondary chamber having openings at its opposite ends connected to saidoutlet for further atomizing the fuel received from said primarychamber, said secondary chamber having an outlet intermediate its ends,means adapted to be connected in communication with the exhaust manifoldof the engine arranged in heating relation to both of said chamberswhereby fuel present in said primary chamber is warmed prior to enteringsaid secondary chamber and whereby the further atomized fuel present insaid secondary chamber is sufficiently heated to pass into gaseous form,an outside air inlet intermediate the ends of said secondary chamber foradmitting air for admixture to the gas present in said secondarychamber, and a conduit leading said outlet of the secondary chamber andentering said carburetor tube for conveying the gas and air mixture intothe carburetor tube.

3. In a device for supplying a mixture of air 'and vaporized liquid fuelto the tube of a carburetor of an internal combustion engine having anexhaust manifold, said device comprising a primary chamber for heatingliquid fuel and having atomizing jets at its opposite ends, a liquidfuel force pump connected in supply relation to the jets of said primarychamber, an outlet intermediate the ends of said primary chamber, asecondary chamber having openings at its opposite ends connected to saidoutlet for further atomizing the fuel received from said primarychamber, said secondary chamber having an `outlet intermediate its ends,means adapted to be connected in communication with the exhaust manifoldof the engine arranged in heating relation to both of said chamberswhereby fuel present in said primary chamber is warmed prior to enteringsaid secondary chamber and whereby 5 the further atomized fuel presentin said secondary chamber is sufficiently heated to pass into gaseousform, an outside air inlet intermediate the ends of said secondarychamber for admitting air for admixture to the gas present in saidsecondary chamber, and a conduit leading said outlet of the secondarychamber and entering said carburetor tube for conveying the gas and airmixture into the carburetor tube, each of said chambers comprising anouter cylindrical shell closed at its ends, and an inner hollow cylinderspaced Within said outer shell to define an exhaust gas space with whichsaid exhaust manifold is connected, said atomizing jets being arrangedin the opposite ends of said inner cylinder. 4. In a device forsupplying a mixture of air and vaporized liquid fuel to the tube of acarburetor of an internal combustion engine having an exhaust manifold,said device comprising a primary chamber for heating liquid fuel andhaving atomizing jets at its opposite ends, a liquid fuel force pumpconnected in supply relation to the jets of said primary chamber, anoutlet intermediate the ends of said primary chamber, a secondarychamber having openings l:at its opposite ends connected to said outletfor further atomizing the fuel received from said primary chamber, saidsecondary chamber having an outlet intermediate its ends, means adaptedto be connected in communication lwith the exhaust manifold of theengine arranged in heating relation to both of said chambers wherebyfuel present in said primary chamber is warmed prior to entering saidsecondary chamber and whereby the further atomized fuel present in saidsec- ILO ondary chamber is suiciently heated to pass into gaseous form,an outside air inlet intermediate the ends of said secondary chamber foradmitting air for admixture to the gas present in said secondarychamber, and a conduit leading said outlet of the secondary chamber andentering said carburetor tube for conveying the gas and air mixture intothe carburetor tube, each of said chambers comprising an outercylindrical shell closed at its ends, and an inner hollow cylinderspaced within said outer shell to dene an exhaust gas space twith whichsaid exhaust manifold is connected, said atomizing jets being arrangedin the opposite ends of said inner cylinder, said jets being arrangedaxially in the ends of the inner cylinders of said primary and secondarychambers, the jets in the ends of the inner cylinder of said secondarychamber` being finer than the primary chamber jets.

5. In combination, a vertical carbureter tube, a pair of housingsmounted on opposite sides o1' said tube and comprising transverselyelongated primary and secondary chambers, means for heating saidchambers, said primary chamber having atomizing jets in its oppositeends, means for supplying liquid fuel to said jets under pressurewhereby fuel is heated and atomized Within said primary chamber, anoutlet on said chamber intermediate its ends, said secondary chamberhaving openings in its opposite ends, a conduit connected to saidprimary chamber outlet having branches extending around opposite sidesof said carbureter tube and connected with the :secondary chamber jetsat opposite ends of said secondary chamber, said secondary chamberhaving a gas outlet intermediate its ends leading directly through theadjacent side of said carbureter tube to convey gas into the carburetertube.

6. In combination, a vertical carbureter tube, a pair of housingsmounted on opposite sides of said tube and comprising transverselyelongated primary and secondary chambers, means for heating saidchambers, said primary chamber having atomizing jets in its oppositeends, means for supplying liquid fuel to said jets under pressure'whereby fuel is heated :and latomized within said primary chamber, anoutlet o-n saidchamber intermediate its ends, said secondary chamberhaving openings in its opposite ends, a conduit connected to saidprimary chamber outlet having branches extending around opposite sides'of said carbureter tube and connected with the secondary chamber jets atopposite ends of said secondary chamber, said secondary chamber having agas outlet intermediate its ends leading directly through the adjacentside of said carbureter tube to convey gas into the carbureter tube, anoutside air inlet traversing the side of said secondary chamber oppositesaid gas outlet at a point intermediate the ends of said secondarychamber.

HENRY J. MCLEOD.

REFERENCES CITED The following references are of record in the le ofthis patent:

Y UNITED STATES PATENTS Number Name Date 572,797 Hathaway Dec. 8, 1896`1,058,660 Davis Apr. 8, 1913 1,189,688 Hansen-Ellehammer July 4, 19161,795,037 Portail Mar. 3, 1931 2,172,537 Hilson et al Sept. 12, 19392,218,922 Newberry Oct. 22, 1940 2,306,897 Ollig Dec. 29, 1942

